3685+200481+958,101030-98104-56,100000-(586+49503),7510+(301296-4098)

1)3685+200481=204166, 2)204166+958=205124; 1)101030-98104=2926, 2)2926-56=2870; 1)49503+586=50089, 2)100000-50089=49911; 1)301296-4098=297198, 2)7510+297198=304708